Subgenus Nannomys. A distinct species sometimes confused with M. minutoides, which occurs over approximately the same region (Rosevear, 1969). Multivariate analysis of morphometric traits by Macholán (2001) indicated that M. setulosus and M. minutoides were distantly related. Both pasha (Thomas, 1910a) and proconodon (Rhoads, 1896) were originally described as species; Osgood (1936) associated pasha with M. proconodon, and we agree with his identification. F. Petter and Matthey (1975) regarded pasha as a species, noting that it might be referrable to M. setulosus. Both Osgood (1936) and Yalden et al. (1976) recognized proconodon as a species endemic to Ethiopia. Our study of Osgood's specimens, some of which are near-topotypes, revealed that their morphological traits fell within the range of variation typical of M. setulosus. Our identification was foreshadowed by F. Petter and Matthey (1975), who cited the range of M. setulosus to include Ethiopia, based on a letter from J. Prevost. Chromosomal data for samples from West Africa documented by Jotterand (1972), Jotterand-Bellomo (1981, 1986), and Matthey (1964).